Rhymes with Good Reason

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Puzzle master Will Shortz quizzes one of our listeners, and has a challenge for everyone at home.

Challenge from February 18: The object of this challenge is to develop nine different mathematical expressions that equal eight. You must use the digits 2, 7 and one other. And that other digit must be a one in the first expression, two in the next expression and so on, up to nine. You can use a digit once and only once in each expression.

You may use the four arithmetic symbols: plus, minus, times and divided by, as well as exponents and decimal points. You may use parentheses as you need them. For example: Using the digits 2, 7 and 1 you can make the expressions 2+7-1= 8.

(The challenge came from Robert Wainwright in New Rochelle, N.Y.)


7 + 2 - 1

7 + (2 / 2)

7 - 2 + 3

7 + (2 * .5)

7 * 2 - 6

(7/ .7) - 2

7.2 + .8 (or 7 + .2 + .8)

(7 + 9) / 2

2 to the power of (7 -4)

Winner: Derek Inksetter of Oak Park, Illinois.

The given expressions are just the winner's solution. Many other combinations are possible.

Challenge from February 25: From Ed Peg, Jr. of Champaign, Illinois. Take the thirteen letter word, Melancholiacs, add the letter R, then re-arrange all the letters to name a famous actress. Who is it?



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